In response to Lucia: you say you've been mugged in broad-daylight before in South Ken by a punter?
Why use an expensive smart phone when meeting clients? If you're adamant to use your iPhone (yes i've seen it in your pics), why not make sure it's insured. If your icloud isn't working properly, take it straight to the Apple Store Genius bar immediately, they'll be able to figure out the problem (for free). If you have a mac or pc, you can easily back up your device to your computer without the need for icloud. I do understand it's a hassle and that you're fearful of your safety, hence why having a phone on you at all times is far more important. Also, the find my iPhone app is handy should someone nick your phone, because you can trace it and erase it. Android phones have similar apps too.
I do think, it is wise to meet in a public place, especially if you're unsure about your clientele and are lacking in security at your apartment. Why not get a small security camera outside your property? Also notify a friend/colleague when you're with a client. Seems you have those judging from your links on your AW page. Better still, meet at a hotel lobby instead of a busy, tourist filled station.
Your phone is your point of contact for your business, it's also your life line. Meeting without a phone - to me, it just seems an odd M.O considering all your other security measures.
When i punt, I usually take a punting phone with me, this assures that if I do get into a dodgy situation (which luckily so far hasn't happened), I won't lose my £700+ phone, but I'm still able to contact the lady I'm meeting or call the police. Likewise, i think you could do this: buy a cheap Pay&Go burner phone is £20ish at Argos + credit.
Like anyone else, you as a WG have a right to defend yourself even on a 'punters' site, but like others have said, make sure you're correct on the facts, else you will be stood corrected and will quickly put would-be punters off, which I know you don't want to do.
Good luck.